1. Field of the Invention
The present invention relates generally to navigation technology, and more particularly, to navigation technology implementing external navigation data storage devices.
2. Related Art
In recent years, navigation systems for use with automobiles have become popular. Such navigation systems typically include a display screen, an input technology such as a keypad or remote control, and a storage technology such as a CD. Geographical map and routing data is typically stored on the CD as a map database.
The map database on the CD can have various levels of detail. At the very least, the map database includes geographical information at the major road level. Additional details that can be included in the map database are major roads, turn restrictions, one-way streets, highway ramp configurations, hotel, restaurant and other business information, traffic history, emergency facility locations, and the like. The data of such map databases with routing information are referred to as navigable map data or turn-by-turn data. The level of detail stored in these map databases depends on product and marketing factors, including cost and demand, as well as physical storage capability limitations.
The described navigation systems are stand-alone devices that rely completely on data stored on a local source device for geographical and other related information. Thus, the capacity of the storage device becomes a limiting factor as to how much information is available to a user. In addition, the user must update the mapping database frequently to stay current. Typically, the cost of mapping databases increases with the amount of detail provided thereon.
Another type of navigation system, that can be used with automobiles, does not use a geographic database installed locally with a navigation system interface unit. Instead, this type of navigation system uses a wireless communication link to access a remote geographic database. This type of navigation system does not require that updated geographic data be obtained from time-to-time, because the remote geographic database can be updated as frequently as needed. However, this type of navigation system is unable to receive timely geographic data from the remote geographic database as a result of the large amount of data that must be transmitted over the wireless communication link. In particular, the geographic data is known to have high overhead, where current wireless communication links are known to have limited data transmission capabilities. Therefore, navigation systems that use remote geographic databases have been for the most part commercially infeasible.
An embodiment of present invention is directed to a method and arrangement for translation of navigation data using a telematics unit. The telematics unit includes an input/output element, a translating element, and a transceiver element. The transceiver element of the telematics unit is interfaced with an offboard navigation database unit and at least one Global Positioning System (GPS) satellite, or a similar system capable of providing up-to-date coordinate data.
The translating element serves at least two functions. First, the translating element receives input destination data, in an original format, from the input/output element. The translating element then translates the input destination data from its original format type to a specific format type. For example, the translating element may translate binary data to American Standard Code for Information Interchange (ASCII), or a compressed format. Second, the translating element also receives data from the transceiver element. The data from the transceiver element includes specific navigation routing data from the offboard navigation database. The translating element is responsible for translating the specific navigation route data into data that is readable by the input/output element.